Growth and photo-response of (110) oriented BaBiO3 films on SrTiO3 (001) substrates

Preferred orientation and optical responses were studied for BaBiO3 films grown by pulsed laser deposition. BaBiO3 films have a monoclinic symmetry I2/m, with the (110) preferred orientation on SrTiO3 (001) substrates. From the transmittance spectra of BaBiO3 films, optical bandgaps were estimated to be around 2.3 eV for direct transition and 2.1 eV for indirect transition. From the photo-response transient characteristics of the film, the decay time of photoconductivity was estimated to be 0.48 sec. The relation between ultraviolet light-induced photoconductivity and film crystallinity is clarified. The photoconductivity became low for BaBiO3 films with high crystalline quality which was the opposite result for the case of TiO2 films.

Automated summary

Preferred orientation and optical responses were investigated for BaBiO3 films grown by pulsed laser deposition. The films exhibited monoclinic symmetry I2/m and a (110) preferred orientation. The estimated optical bandgaps were around 2.3 eV for direct transition and 2.1 eV for indirect transition. The decay time of photoconductivity was found to be approximately 0.48 sec. The relationship between ultraviolet light-induced photoconductivity and film crystallinity was clarified, with high-quality crystalline BaBiO3 films exhibiting lower photoconductivity, contrary to TiO2 films.